City of London
As the City's boundaries have remained almost unchanged since the Middle Ages, it is now only a tiny part of the metropolis, though it remains a notable part of central London, holds city status in its own right, and is a separate ceremonial county....

The [City of London] Corporation is headed by the Lord Mayor of the City of London, an office separate from [[and much older than) the Mayor of London.
It gets insanely complicated. The [[Secret) City of London: